I believe that a war may be good depending on the reason. If the result of war is selfish or economical(ex.a country having more lands or something like that) then it is a bad war, but if a war has a good reason(ex.free a race) then you can say it is worth it.There is of course the possibility of being an evil genius who wants to rule the world then the war would be good only for you. Last but not least there is a kind of war where no one knows what's he fighting for and people and civilians are killed for no reason.